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I was taught that small numbers should be written with letters and not numerals. For example "5" would be "five". I've heard conflicting rules and am wondering what the largest number that should be spelt out and not written with digits is? Is it really a matter of opinion or is there a general consensus?
Also, when writing ordinal numbers what is the largest that should be written as opposed to spelt? For example 1,000th vs one-thousandth.